Frame Sizing for Bikepacking Newb?

[wbargz]

I'm a relatively seasoned bike tourer, and have a little bit of experience mountain biking. I like both and am pretty stoked on bikepacking. I'm ready to buy a bike that can help me get into mountain biking, but definitely be ready to handle bikepacking as soon as I'm ready for it.

A question that has come up for me is about frame sizing. I'm planning on buying a Salsa El Mariachi. I'm right at the cusp between medium and large according to their size recommendations at 5' 10.5". At my height, they advise a medium, but a cm taller and they say to go for a large.

On a road bike, I've always liked to lean towards the smaller side. I'm inclined to do so for a mountain bike as well, but it also seams like the packing possibility is higher with the larger frame. Also, I know nothing about buying a mountain bike, so I thought I'd ask for your advice.

What do y'all think? Is there a reason to not go with my gut to go on the smaller side?

Also, I realize that you guys are all going to tell me to test ride like crazy, but for various reasons, I'm buying mail order and do not want to task local shops with sizing me for a bike that I will not be buying from them. I'll also be buying stock but am ready to replace stems, cranks, handlebars etc. until the bike feels right.

[fotooutdoors]

Check out http://www.competitivecyclist.com/za/CCY?PAGE=FIT_CALCULATOR_INTRO for a fit calculator.  You probably want a fit thatis a bit less aggressive than cross-country, though it depends what type of routes you are riding your flexibility, etc.

5'10" is not really diagnostic unto itself.  What is your inseam?  I have a long inseam for my height, so I need to size on the short side; you can easily move your seat up and down, but shortening the top tube is impossible (though you can fine-tune it with stem, it also messes with steering feel).  FWIW, I am comfortable on my large fargo at 5'11", but I test road both large and medium before going that route, as I too am on the cusp.  Good luck!

[stumpyfsr]

You won't pack a lot more on large frame than on the medium. Since this is will be your singletrack shredder and ocassional tourer, I'd go with Medium (the one you more comfortable on).
Good luck

[wbargz]

Thanks for the tips, you guys.

I'm gonna go with the medium, and I'm stoked.

[wbargz]

Yes, this thread was from more than six months ago, but I wanted to share that I just finally picked up a 2013 El Mariachi from Tree Fort for a really solid price, and I finally have a mountain bike.

Finally, I can stop pretending my CrossCheck is a mountain bike.

Thanks for the tips.